I've downloaded a 200MB file from Google Chrome. It took fairly short time for the download to reach 100% (a couple of minutes), but when it reached 100%, it stays at 100% for a long time before saying that the download is finished and renaming the file extension from .crdownload to the real extension of the file (in this case .zip). Why does the download go fairly quickly before reaching 100% and then stay at 100% for a long time?